tepples writes: "Anybody who has redistributed GNU Emacs software since 2009 has inadvertently committed copyright infringement according to this story on The H. The copyright license of Emacs requires distribution of the program's source code, defined as "the preferred form of the work for making modifications". But sometime around 2009, some compiled parser files from CEDET were checked in without the grammars from which they were generated, resulting in a technical violation of the GPL."